1. Field of the Invention
The present invention relates to a structure for mounting a semiconductor part adapted for various kinds of electronic devices or electronic circuit units and a method of manufacturing a mounting substrate used therein.
2. Description of the Related Art
A conventional structure for mounting a semiconductor part will be described with reference to the accompanying drawings. FIG. 15 is an enlarged cross-sectional view of main parts related to the conventional structure for mounting the semiconductor part and FIG. 16 is a plan view of main parts of a mounting substrate, for illustrating a configuration of a land portion in the conventional structure for mounting the semiconductor part.
Next, a configuration related to the conventional structure for mounting the semiconductor part will be described with reference to FIGS. 15 and 16. A mounting substrate 51 includes an insulating substrate 52, a wiring pattern 53 provided on the insulating substrate 52, and a land portion 54 provided at an end of the wiring pattern 53.
The wiring pattern 53 and the land portion 54 are simultaneously formed by etching a metal film and the land portion 54 includes a plurality of island portions 54a. An edge of each island portion 54a forms a vertical plane from the insulating substrate 52 to an upper surface of the island portion.
A plurality of electrodes 56 are provided on a lower surface of the semiconductor part 55 and bumps 57 are attached to the electrodes 56. The bumps 57 attached to the electrodes 56 are thermally compressed on the land portion 54 such that the semiconductor part 55 is mounted on the mounting substrate 51.
Furthermore, an underfill 58 is inserted between the lower surface of the semiconductor part 55 and an upper surface of the insulating substrate 52 to strongly mount the semiconductor part 55, thereby configuring the conventional structure for mounting the semiconductor part (For example, see Patent Document 1).
However, in the conventional structure for mounting the semiconductor part, since the bump 57 is attached to the land portion 54 in a state that the edge of the island portion 54a of the land portion 54 forms the vertical plane, when the underfill 58 expands or contracts, the bump 57 is detached from the land portion 54.
In addition, in a conventional method of manufacturing the mounting substrate 51, since the wiring pattern 53 and the land portion 54 are formed by etching the metal film provided on the insulating substrate 52, the edge of the island portion 54a of the land portion 54 forms the vertical plane. Thus, when the underfill 58 expands or contracts in a state that the bump 57 is attached to the land portion 54, the bump 57 is detached from the land portion 54.
In the conventional structure for mounting the semiconductor part, since the bump 57 is attached to the land portion 54 in the state that the edge of the island portion 54a of the land portion 54 forms the vertical plane, there is a problem that, when the underfill 58 expands or contracts, the bump 57 is detached from the land portion 54.
In addition, in a conventional method of manufacturing the mounting substrate 51, since the wiring pattern 53 and the land portion 54 are formed by etching the metal film provided on the insulating substrate 52, the edge of the island portion 54a of the land portion 54 forms the vertical plane. Thus, there is a problem that, when the underfill 58 expands or contracts in the state that the bump 57 is attached to the land portion 54, the bump 57 is detached from the land portion 54.